# NTSB ANC84LA178: Piper PA-11, N4801M, Tasnuna Valley, AK, September 13, 1984

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: September 13, 1984, 06:00 local (14:00 UTC)
- Place: Tasnuna Valley, AK
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 4372
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC84LA178
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/4372/pdf
- Page: https://openairdocs.org/ntsb/ANC84LA178

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - in flight, maneuvering
  - aircraft handling - improper, pilot in command (cause)
  - stall - inadvertent, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE PLT STATED THAT THEY HAD JUST TAKEN OFF FROM A GRAVEL BAR WHEN THEY SPOTTED A MOOSE. HE CIRCLED THE MOOSE IN A LEFT ORBIT AT ABOUT 65 MILES PER HOUR. DURING ONE OF THE ORBITS THE 'RIGHT WING FELL IN A DOWNWARD DIRECTION AND THE NOSE OF THE ACFT PITCHED DOWN AND THE AIRPLANE FELL TO THE GROUND.'

## Aircraft

- Registration: [N4801M](https://openairdocs.org/deregistered/N4801M-2012-06-12), registration cancelled 2012-06-12, S/N 11-314, built 1947 (OpenAirDocs)
- Reported make and model: PIPER PA-11
- Registry model: [Piper PA-11](https://openairdocs.org/model/piper-pa-11) (registry code 7101102) (OpenAirDocs)
- Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs)
- Category: Airplane
- Serial number: 11314
- Airframe hours: 1164
- Engines: LYCOMING O-235-C1 115 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Robert Pierson
- Airworthiness certificate: Standard, Normal
- Departed: VDZ, VALDEZ, AK

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 1,124 total, 1,124 in this make and model, 1,124 as pilot in command, 250 in the last 90 days, 150 in the last 30 days, 9 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 43 °F, dew point -0 °F
- Altimeter: 29.00 inHg

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19840913051029A](https://openairdocs.org/incident/19840913051029A), Sep 13, 1984: Piper PA11, Tasnuna Valley, AK, Substantial damage. Circled moose at low altitude and airspeed. Aircraft stalled, impacted ground.

## Other investigations on N4801M (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB UNK64X3889](https://openairdocs.org/ntsb/UNK64X3889), Sep 9, 1964: Piper PA11 (N4801M), Nebesna, AK, substantial damage

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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